88 Turbo runs bad on startup

[AZ88Turbo]

When I start my 88 from cold it runs very bad, I have to let the water temp come up to about 70 before it will run good. Someone told me there is a baffel on the turbo that is on until it warms up. Is this correct?

Also I noticed that a hose clamp from the turbo to the intake manifold is loose and there is oil (that is what it looks like) leaking out. Could this have anything to do with bad performance?

Thanks for your help.

AZ88Turbo

[cnh1990]

Depending on how much you have on the clock the turbo bearing might spew a little oil. Clamp the hose down it is not supposed to be loose. Tell us more about the car and what you regard as from cold?
Calvin

[az88turbo]

Hi,

Thanks for the response.

When I start the car from cold (when it starts) it runs very "lumpy" or sounds like it is missing. It will not idle, I have to keep it at about 2500rpm or it cuts out. When it reaches about 80 degrees (water temp) it revs high for a second, then it idles at about 1000rpm ok. Even when it has got to this stage, if you go out and use the turbo it cuts out when I get to a light or stop sign, then it is very difficult to start again. When it has been running for 15 - 20 mins. it runs very well and there are no problems. I fixed the hose on the turbo but notice now that I am only getting about 4 bar on the boost gauge (less than half on the gauge). If you have any ideas I would appreceate your response. The car has less than 24k miles on it and it is in excellent condition.

Thanks in advance for your help.

Mark (az88turbo).

[cnh1990]

Go ahead and check the obvious stuff first.
Plugs, wires, fuel filter, etc. Check for vac leaks. Seems the warm up idle is not working right. Does your car have an EBPV device just ahead of the muffler? Robert who goes under the screen name Swedish Surgeon in very good with Bosch injected cars and is a professional mechanic by trade.
Calvin

[AZ88Turbo]

Hi Calvin,

I have checked the plugs, wires etc. The plugs are a light brown colour (which is good I believe) and I can't see any arching out with the HT leads or anything. I'm not sure where the fuel filter is (I'll have to check the book). Where and what should I look for with the vacuum stuff? I am also not sure what the EBPV device looks like or what it does, can you explain a little please?

I contacted the local Lotus dealer (the only one in the state) and I wasn’t impressed with their level of knowledge at all. Quite scary actually, they asked questions like “is that a V8”, this is after I told them it is an 88 model, they also asked “which belt is that” in answer to the question “how much would it cost to get the cam belt changed”. I guess they don’t see too many older Lotus.

Anyway, I really would like to figure out what is going on with this thing.

Does anyone have any ideas why the turbo boost is low? Does it mean the turbo is on its way out?

Thanks in advance for any help you can provide.

Mark (AZ88Turbo)

[lotusguy]

Mark,

Your problems can be caused by several faulty items or multiples thereof. First, your throttle jacking solenoid may not be operating properly. Be sure it energizes when the engine is cold and that it is adjusted properly to that it acts on the throttle spindle lever when energized.

Other culprits could be your thermal time switch, low temperature switch or high temperature switch. You can either create a jumper connected to both the switch and a multimeter and read the switches in place, look for voltage when temp is low (<70°F)and voltage falloff once temp is up(>70°F).

Or, you can remove each of these and immerse their sensor ends in warm liquid and watch a continuity reading on a multimeter. Look for continuity when cold (<70°F) and open circuit once warmed up(>70°F). Hope this helps. Happy Motoring!...Jim'85TE

[az88turbo]

I'll start to check this stuff systematically.

Thanks for all your help and taking the time to write the replies.

Mark

[az88turbo]

Looking through service book; I just noticed that before an idle ajustment is made you have to loosen the throttle sensor switch. I made a slight adjustment to this the other day and didn't loosen it, and if I think about it that is when the Turbo boost dropped. I wonder if the butterfys are out of whack and that is what is causing the boost issue? I don't think it solves the starting issue though as it was doing that before.

[lotusguy]

az88turbo said: Looking through service book; I just noticed that before an idle ajustment is made you have to loosen the throttle sensor switch. I made a slight adjustment to this the other day and didn't loosen it, and if I think about it that is when the Turbo boost dropped. I wonder if the butterfys are out of whack and that is what is causing the boost issue? I don't think it solves the starting issue though as it was doing that before.

Mark,

It's doubtful that this caused the boost problem you are experiencing as the throttle position sensor merely sends a signal to the ecu to enrich the fuel supply on idle. However, if ot restricted the full range of the 'butterflies' it could well have contributed, and it can cause idle problems as it may not allow the ECU to enrich the fuel as necessary for a smooth idle.

As long as you have the manual, take time to thoroughly study and understand the Bosche k-Jetronic system before monkeying around with it. k-Jetronic is basically a very good system (Ferrari and MB used it extensively), but it uses a delicate balance of settings from various sensors to work properly. It is not a truly dynamic EFI system as is is basically a mechanical FI system using electronic sensors to adapt itself to demand conditions (the 'k' in k-Jetronic stands for the German word Konstant, which means continuous), the fuel injectors send a constant stream of fuel into the intake manifold. The system relies rather heavily on temperature changes to regulate the fuel supply to the injectors which is why you have so many thermal switches. When it's goofing up, these are always the most likely suspects. Hope this helps. Happy Motoring!...Jim'85TE

[AZ88Turbo]

Hi Jim,

That is very good advise. I will indeed study and learn this stuff. I hope one day to know my Lotus inside out and be able to do most of the maintenance myself.

Regards,

Mark

[swedishsurgeon]

Hi Mark,
I have an idea on what is wrong with your car but would need to know more information. If you would like to give me your phone number, please email me at:
[e-mail] and I'll give you a call.
Cheers,
Robert

[lotusguy]

swedishsurgeon said: Hi Mark,
I have an idea on what is wrong with your car but would need to know more information. If you would like to give me your phone number, please email me at:
[e-mail] and I'll give you a call.
Cheers,
Robert

Bob,

Please share your pearls of wisdom and experience with us all. That's what this forum is for. I know how knowledgeable you are on Bosche FI and I'm anxious to learn from you too. Happy Motoring! Jim'85TE